Design of high performance thickener hydrocyclones using robust optimization

In the literature, a large number of works about the hydrocyclones geometry optimization to obtain high performance separators can be found. However, in these works, during the optimization process, no uncertainties in model, design variables and/or parameters are considered. In these cases, a small variation in the design variable vector can result in a meaningful change on the theoretical optimal design as represented by the minimization of the corresponding vector of objective functions. In this contribution, the Effective Mean Concept is associated with the Multi-Objective Optimization Differential Evolution to obtain solutions less sensitive to perturbations in the design variables during the thickener hydrocyclones design. For this purpose, the proposed multi-objective optimization problem considers the determination of geometric variables to maximize hydrocyclone's total efficiency (eta), to minimize the underflow-to-throughput ratio (R-L) and to minimize the Euler number (Eu). The robust results are compared with those obtained considering nominal context (without robustness). The results showed that the tested hydrocyclones present good thickener equipment and that the robust Pareto's curve presents less diversity in comparison with the nominal solution.